Scope for growth in Gammarus pulex, a freshwater benthic detritivore

"Scope for growth', the difference between the energy input to an organism from its food and the output from respiratory metabolism, can give a good physiological measure of stress that in principle is straightforwardly related to population and community processes. In Gammarus pulex (Crustacea, Amphipoda), both Zn and low pH can significantly reduce the scope for growth of individuals; the most sensitive component of the energy budget is food absorption. -from Authors